LT3798 ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operatingtemperature range, otherwise specifications are at TA = 25°C. VIN = 18V, INTVCC = 11V, unless otherwise noted.PARAMETERCONDITIONSMINTYPMAXUNITS SENSE Current Limit Threshold VIN_SENSE = 150µA 96 102 107 mV Minimum SENSE Current Limit Threshold VIN_SENSE = 34µA 14 mV Minimum SENSE Current Limit Threshold VIN_SENSE = 21µA 4 mV SENSE Input Bias Current Current Out of Pin, SENSE = 0V 15 µA FB Voltage l 1.22 1.25 1.28 V FB voltage Line Regulation 10V < VIN < 35V 0.01 0.03 %/V FB Pin Bias Current (Note 3), FB = 1V 4.05 4.25 4.4 µA FB Error Amplifier Voltage Gain ΔVVC/ΔVFB, CTRL1=1V, CTRL2=2V, CTRL3=2V 180 V/V FB Error Amplifier Transconductance ΔI = 5µA 170 UMHOS Current Error Amplifier Voltage Gain ΔVCOMP+/ΔVCOMP–, CTRL1 = 1V, CTRL2 = 2V, CTRL3 = 2V 100 V/V Current Error Amplifier Transconductance ΔI = 5µA 50 UMHOS Current Loop Voltage Gain ΔVCTRL/ΔVSENSE,1000pF Cap from COMP+ to COMP– 21 V/V DCM Current Turn-On Threshold Current Out of Pin 80 µA Maximum Oscillator Frequency COMP+ = 0.95V, VIN_SENSE = 150µA 150 kHz Minimum Oscillator Frequency COMP+ = 0V, VFB <VOVP 4 kHz Minimum Oscillator Frequency COMP+ = 0V, VFB >VOVP 0.5 kHz Backup Oscillator Frequency 20 kHz Linear Regulator INTVCC Regulation Voltage No Load 9.8 10 10.4 V Dropout (VIN-INTVCC) IINTVCC = –10mA, VIN = 10V 500 900 mV Current Limit Below Undervoltage Threshold 12 25 mA Current Limit Above Undervoltage Threshold 80 120 mA Gate Driver tr GATE Driver Output Rise Time CL = 3300pF, 10% to 90% 18 ns tf GATE Driver Output Fall Time CL = 3300pF, 90% to 10% 18 ns GATE Output Low (VOL) 0.01 V GATE Output High (VOH) INTVCC- V 50mV Note 1: Stresses beyond those listed under Absolute Maximum Ratings LT3798I is guaranteed to meet specified performance from –40°C to 125°C may cause permanent damage to the device. Exposure to any Absolute operating junction temperature range. The LT3798H is guaranteed to meet Maximum Rating condition for extended periods may affect device performance specifications over the –40°C to 150°C operating junction reliability and lifetime. temperature range. The LT3798MP is guaranteed to meet performance Note 2: The LT3798E is guaranteed to meet specified performance from specifications over the –55°C to 150°C operating junction temperature 0°C to 125°C junction temperature. Specification over the –40°C and range. High junction temperatures degrade operating lifetimes. Operating 125°C operating junction temperature range are assured by design, lifetime is derated for junction temperatures greater than 125°C. characterization and correlation with statistical process controls. The Note 3: Current flows out of the FB pin. 3798fa 3 Document Outline Description Features Applications Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Typical Applications Package Description Revision History Typical Application Related Parts